Dental operating light

ABSTRACT

A lamp primarily for use as a dental operating lamp which comprises an annular frame which is connected to an arm for mounting the lamp on a support, a light source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of the frame and a plurality of annular convection fins removably mounted on both sides of the frame in spaced relationship to one another so as to surround the light source and lens system while allowing an uninterrupted passage for convection currents in substantially all radial directions around the light source. The convection fins are preferably dished so as to form a shade for the light source without impeding the air flow and the lamp is preferably mounted on a support comprising a tubular arm which is adapted to form a continuous conduit for a flexible cable and which includes two joints along the lamp to be rotated through at least 330* about each of two mutually perpendicular axes which axes are preferably both perpendicular to and pass through the optical axis of the lamp.

United States Patent Rosen et al.

[451 Sept. 5, 1972 DENTAL OPERATING LIGHT Filed: Oct. 7,'l970 Appl. No.:78,681

US. Cl ..240/4l.l5, 240/413 Int. Cl. ..A6lb l/06 Field of Search..240/41 .15, 46.41 47, 41.3

References Cited UNITED STATES PATENTS 1,884,265 10/1932 Rush ..240/47 XPrimary Examiner-Jerry W. Myracle Attomey-Hopgood & Calimafde Sandoe[57] ABSTRACT which comprises an annular frame which is connected to anarm for mounting the lamp on a support, a light source and lens systemmounted on the annular frame with the optical axis of the lens systemgenerally aligned with the axis of the frame and a plurality of annularconvection fins removably mounted on both sides of the frame inspacedrelationship to one 1 another so as to surround the light source andlens system while allowing an uninterrupted passage for convectioncurrents in substantially all radial directions around the light source.The convection fins are preferably dished so asto form a shade for thelight source without impeding the air flow and the lamp is preferablymounted on a support comprising a tubular arm which is adapted to form acontinuous conduit for a flexible cable and which includes two 1 jointsalong the lamp to be rotated through at least 330 about each of twomutually perpendicular axes which axes are preferably both perpendicularto and pass through the optical axis of the lamp.

13 Claims, 3 Drawing Figures 6O Mun. if 9 62 um 61 i 72 71 Z llllll l 0'M 70 e9 74 66 43a A 63 z N\ i 56 52d PATENTEDSEP 5|97Z 3,689,761

SHEET 2 [IF 2 Inventors Cyril Rosen and Stan Patok Attornovs Sandoe,Hopgood 5; Calima ma DENTAL OPERATING LIGHT BACKGROUND TO THE INVENTIONKnown dental operating lamps have the disadvantage that they generate aconsiderable amount of heat which is not effectively dissipated in allof the angular positions in which the lamp is used and cannot,therefore, always be positioned close to the patients mouthJhey are alsorelatively bulky because they incorporate a separate bulb and reflectorand in many cases they are not fully adjustablein both horizontal andvertical' STATEMENT OF THE INVENTION According to the present inventionthere is provided a lamp, for use as an operating lamp, comprising anannular frame, means for mounting the lamp, a light source and lenssystem mounted on the annular frame with the optical axis of the lenssystem generally aligned with the axis of the frame a plurality oflongitudinal members projecting from each side of the frame in parallelwith the axis of the frame and a plurality of annular convection finsremovably mounted on the said longitudinal members in spacedrelationship so as to surround the light source and allow anuninterrupted passage for convection currents in substantially allradial directions from the light source.

According to a further aspect of the invention there is provided a lampas defined in the preceding paragraph, wherein the said means formounting the lamp comprises a tubular arm forming a continuous conduitfor a flexible cable and including two joints allowing the lamp to berotated through at least 330about each of two mutually perpendicularaxes.

Preferably, the said mutually perpendicular axes are both perpendicularto and pass through the optical axis of the lamp.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal section through alamp according to the present invention,

FIG. 2 is an end elevation of the lamp of FIG. 1, showing the supportingarm in vertical section, and

FIG. 3 is a section, taken on the line III-III in FIG. 1 of a detail ofthe lamp.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, a dentaloperating lamp is indicated generally at supported on a freelyadjustable arm, which is indicated generally at 11.

The arm 11 comprises a ball 12 which is mounted in a fixed tubularsupport 13 so as to be rotatable in a vertical plane within limitsimposed by the abutment of a stem 14 against an end 15 of the tubularsupport 13. The stem 14 joins the ball 12 to a tubular bush 16 in whicha tubular member 17 is rotatably mounted. The tubular member 17 isattached in the bush 16 by a spacer 18 and friction adjusting nuts 19,20 which are threaded on the the end of the tubular member 17. Locatedbetween the bottom end of the spacer l8 and the bush 16 are a flatwasher 21, spring washer 22 and friction washer 23. By adjusting thenuts 19, 20, the frictional resistance to rotation of the tubular member17 within the bush 16 can be varied. The adjusting nuts 19 and20 arehidden by a cap 24 which is threaded on to the upper end of the bush 16.A friction washer 25 is located between the bottom surface of the bushl6 and a co-operating surface of the member 17 and a channel 26 isformed in the upper surface of the tubular member 17. The channel 26houses two pins, not

shown, one fixed to the bush 16 and the other fixed to the tubularmember 17 which allow rotation of the member 17 relative to the bush 16through at least 330and not more than 360.

A tubular rod 27 is attached integrally to the tubular member 17 andprojects at an angle to the axis of rotation of the member 17 anddownwardly therefrom. The rod 27 is cranked intermediate its length anda bush 28, which is provided with a tubular switch housing 29 for anelectrical switch is mounted on the bottom end of the rod 27. A tubularspigot 30 is mounted for rotation in the lower bush 28 in the samemanner as the tubular member 17 is mounted in the bush 16. A pairoffriction adjusting nuts 31, 32, spacer 33, flat washer 34, springwasher 35 and friction washer 36 control the frictional resistance torotation of the tubular spigot 30 within the bush 28 and a cap 37 isprovided to hide the nuts 31, 32 and prevent the entry of dust and dirt.A friction washer 38 is provided between the tubular spigot 30 and lowerbush 28 and pins 39 and 40 mounted respectively on the lower bush 28 andspigot 30 so as to project into a groove 41 in the tubular member 30,allow for rotation of the spigot 30 through at least 330 and not morethan 360 relative to the lower bush and about the axis of the spigot 30.

It will be seen from the above description of the arm 11 that the lamp10 can be rotated about the two mutually perpendicular axes of thetubular member 17 and the tubular spigot 30 and that the tubular member17 is perpendicular to and passes through the optical axis of the lamp10 because of the crankin the rod 27.

It will furthermore be seen that a continuous conduit is formed from thetubular support 13 through the ball 12, tubular member 17, rod 27,tubular switch housing A tubular extension 42 of the spigot 30 is aforced fit into any one of a plurality of tubular radial bores 43aprovided in an annular frame 43, which is shown in sec-, tion in FIG. 1.The frame 43 is provided with a central aperture 44 and threeequi-angularly arranged axial holes 45, only one of which is shown, andeach of which is adapted to receive a rod 47 which forms a part of aconvection fin mounting assembly.

There are three similar fin assemblies 48, 48a and 48b and only theassembly 48 will be described in detail. The assembly 48 comprises therod 47 which extends through the hole 46 in the ring 43 and which isfixed in position by a transverse grub screw 49. Mounted on each end ofthe rod 47 are sleeves 50 and 29 and tubular spigot 30 for a cableleading to the lamp 51. The sleeve 50 carries six convection fins 52a,52b, 52c, 52d, 52e, 52f and the sleeve 51 carries three convection fins53a, 53b and 53c. The fins 52 and the fins 53 are separated from oneanother by tubular spacers 54 which are slidably mounted on the sleeves50 and 51.

The fins 52 and 53 are substantially similar and each comprises a flatannular base portion 55 which is formed with three circular holes toreceive the rods and sleeves and a dished outer wall or flange 56.

Nuts 57 and 58 are threaded on to the outer ends of the two sleeves 50and 51 respectively and retaining dome nuts 59 and 60 are threaded on tothe threaded ends 61, 62 respectively of the rod 47 to complete theassembly.

A light retaining ring 63 is mounted in the e base of the fin 52andsupports a tungsten-halogen light 64. The light 64 carries a built-indichroic reflector and a suitable light of this type carrying a built-inreflector is that sold by Philips Electrical Company under SCIYNO.6,834. The light 64 is held in position on the ring 63 by a lightretaining spring 65.

Mounted on the rear end of the light 64 is a light connector 66 which iselectrically connected to a terminal block 67. The terminal block 67 ismounted on the base portion 55 of the fin 53a by a screw 68 and nut 69.The fin 53a has a central aperture of diameter sufficient to receive thescrew 68 and is also provided with a plurality of small apertures 55afor the passage of air. A terminal block cover 70 is mounted over theterminal block with the aid of a domed nut 71 which is engaged on theend of the screw 68. As can be seen from FIG. 1, a cable 72 emerges fromthe spigot 30 and is connected to the terminal block 67 Mountedforwardly of the light 64 is a mask 73 having a variable aperture 74.The mask 73 is mounted in a mask-retaining ring 75 which is itself apush fit into the base portion of the fin 52c.

Mounted forwardly of the mask 73 is a lens 76 which is fixedly mountedin a tubular lens support 77. The lens support 77 is threadedlyengagedin a lens bush 78 which is itself a push fit mounting in the base of theleading fin 52a. The position of the lens 76 on the axis of the lamp isadjustable by threading the lens support inwardly or outwardly and isfixed in position by a transverse grub screw 79.

On the opposite side of the light 64 to the tubular spigot 30, a handle80 is provided which is mounted on a spigot 81 which is a push fit in aradially positioned hole in the light assembly retaining ring 43. Itwill be appreciated that the dished outer wall of the fin 53c isprovided with cut-outs to accommodate the spigot 30 on one side and thespigot 81 on the other side of the lamp.

In order to connect the lamp to a source of current, a cable (not shown)is fed through the arm 11 to an electrical switch unit (not shown) whichis housed in the switch housing 29. From the switch unit, cable 72 leadsto the terminal block 67 which is electrically connected to the light64.

When the lamp is in use, the heat generated by the bulb in the light.64creates convection currents of air which pass upwardly in the directionof the arrows through the fins past the bulb and upwardly and outwardlyfrom the upper side of the lamp. The convection currents which aregenerated by the bulb carry the heat of the bulb away and enable thelamp to be used in close proximity to the patients mouth and at anyangle without impeding the flow of air around the bulb. The dishedshaped of the fins also has the advantage that side-dazzle by the lightemitted by the bulb is eliminated or at least reduced while leaving aclear passage for the convection currents of air which are not impededinany way regardless of the angle of the lamp.

The adjustments which can be made in horizontal and vertical planes tothe lamp give exceptional flexibility in the positioning of the lamp andenable any area of the patients mouth to be illuminated with thepatients head in any position. If the lamp is positioned with theoptical axis directed vertically downwardly then the convection currentsescape through the holes 550 in the rear fin 53a.

The light 64, with its own built-in reflector enables the lamp to bemade relatively small while the lens system gives an optimum illuminatedarea of approximately 3 X 5 A inches with a sharp outline.

in order to replace the light 64 all that is necessary is to remove thefin assembly nuts 59 of the three convection fin assemblies 48, 48a,48b. The complete front fin assembly comprising the fins 52a 52f, theassociated spacers 54 and the sleeves 51 of the three fin assemblies,isthen drawn away from the rods 47 carrying the light 64 with it. Thebulb of the light 64 can then be replaced and reassembled. Alternativelythe rear fin assembly can be removed to give access to the back of thelight 64 by removing the three rear fin assembly units 60 andwithdrawing the fins 53a 53c and the associated spacers 54 and sleeves51.

It will be seen from the above that the structure of the dentaloperating lamp of the present invention provides quick and easy accessto the light 64 for servicing and replacement, that side dazzle from thelight emitted is eliminated or at least substantially reduced and thatthe heat generated by the bulb is efficiently dissipated by theconvection currents which flow freely through the lamp in the region ofthe bulb regardless of the position in which the lamp is placed.

Further minor modifications can be made to the above describedembodiment without departing from the spirit and scope of the inventionwhich is best described in the following claims.

What we claim is:

l. A lamp for use as an operating lamp, comprising an annular frame, asupport, means for mounting the frame of the lamp on said support, alight source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of theframe, a plurality of annular convection fins removably mounted on theframe in spaced relationship so as to surround the light source andallow an uninterrupted passage for convection currents in substantiallyall radial directions from the light source, wherein the convection finsare dished so as to form a shade for the light source without impedingthe air flow around the light source, wherein a plurality oflongitudinal members project from each side of the frame in parallelwith the axis-of the frame and a plurality of the said convection finsare removably mounted on the members on each side of the frame.

2. A lamp as claimed in claim 1, wherein the convection fins on eachside of the annular frame are mounted on the longitudinal members so asto be removable as a single unit to give easy access to the front orrear of the lamp respectively.

3. A lamp as claimed in claim 2, wherein the longitudinal memberscomprise rods extending through the annular frame so as to project fromeach side thereof, a sleeve is slidably mounted on each end of each rodand the convection fins are mounted on the sleeves so as to be removablewith the sleeves.

4. A lamp as claimed in claim 3, wherein each convection fin comprises asubstantially flat annular base and a dished annular flange projectingoutwardly therefrom.

5. A lamp as claimed in claim 4, wherein the base of each convection finis formed with a plurality of first apertures to receive the sleeves onwhich each fin is mounted.

6. A lamp as claimed in claim 5, wherein the rear cone has a base formedwith a plurality of second apertures for the passages of convectioncurrents therethrough.

7. A lamp as claimed in claim 6 wherein the convection fins areseparated by tubular spacers slidably mounted on the sleeves.

8. A lamp as claimed in claim 7, wherein three angularly spacedlongitudinal members project from each side of the annular frame.

9. A lamp as claimed in claim 1, wherein said means for mounting thelamp on said support comprises a tubular arrn forming a continuousconduit and includes two joints allowing the lamp to be rotated throughat least 330 about each of the two mutually perpendicular axes.

10. A lamp as claimed in claim 9, wherein thesaid mutually perpendicularaxes are both perpendicular to and pass through the optical axis of thelamp,-

1 1. A lamp as claimed in claim 10, wherein the tubular arm includes atubular spigot which projects radially from the annular frame and ismounted on the outer end of an intermediate arm portion so as to berotatable, relative thereto, about its own axis through at least 330.

12. A lamp as claimed in claim 11, wherein the intermediate arm portionis mounted on a bush so as-to be rotatable, through at least 330 aboutan axis perpendicular to the axis of the spigot and to the axis of thelamp.

13. A lamp as claimed in claim 12, wherein the inter- I mediate armportion is cranked, whereby the axis about which the intermediate armportion is rotatable is offset from the point at which the spigot isjoined to the intermediate arm portion.

1. A lamp for use as an operating lamp, comprising an annular frame, asupport, means for mounting the frame of the lamp on said support, alight source and lens system mounted on the annular frame with theoptical axis of the lens system generally aligned with the axis of theframe, a plurality of annular convection fins removably mounted on theframe in spaced relationship so as to surround the light source andallow an uninterrupted passage for convection currents in substantiallyall radial directions from the light source, wherein the convection finsare dished so as to form a shade for the light source without impedingthe air flow around the light source, wherein a plurality oflongitudinal members project from each side of the frame in parallelwith the axis of the frame and a plurality of the said convection finsare removably mounted on the members on each side of the frame.
 2. Alamp as claimed in claim 1, wherein the convection fins on each side ofthe annular frame are mounted on the longitudinal members so as to beremovable as a single unit to give easy access to the front or rear ofthe lamp respectively.
 3. A lamp as claimed in claim 2, wherein thelongitudinal members comprise rods extending through the annular frameso as to project from each side thereof, a sleeve is slidably mounted oneach end of each rod and the convection fins are mounted on the sleevesso as to be removable with the sleeves.
 4. A lamp as claimed in claim 3,wherein each convection fin comprises a substantially flat annular baseand a dished annular flange projecting outwardly therefrom.
 5. A lamp asclaimed in claim 4, wherein the base of each convection fin is formedwith a plurality of first apertures to receive the sleeves on which eachfin is mounted.
 6. A lamp as claimed in claim 5, wherein the rear conehas a base formed with a plurality of second apertures for the passagesof convection currents therethrough.
 7. A lamp as claimed in claim 6wherein the convection fins are separated by tubular spacers slidablymounted on the sleeves.
 8. A lamp as claimed in claim 7, wherein threeangularly spaced longitudinal members project from each side of theannular frame.
 9. A lamp as claimed in claim 1, wherein said means formounting the lamp on said support comprises a tubular arm forming acontinuous conduit and includes two joints allowing the lamp to berotated through at least 330* about each of the two mutuallyperpendicular axes.
 10. A lamp as claimed in claim 9, wherein the saidmutually perpendicular axes are both perpendicular to and pass throughthe optical axis of the lamp.
 11. A lamp as claimed in claim 10, whereinthe tubular arm includes a tubular spigot which projects radially fromthe annular frame and is mounted on the outer end of an intermediate armportion so as to be rotatable, relative thereto, about its own axisthrough at least 330*.
 12. A lamp as claimed in claim 11, wherein theintermediate arm portion is mounted on a bush so as to be rotatable,through at least 330* about an axis perpendicular to the axis of thespigot and to the axis of the lamp.
 13. A lamp as claimed in claim 12,wherein the intermediate arm portion is cranked, whereby the axis aboutwhich the intermediate arm portion is rotatable is offset from the pointat which the spigot is joined to the intermediate arm portion.